It often feels fruitless to pick out the strongest aspects of the Carlos Alcaraz game. (Sinner’s, too, of course.) He is so good at everything that we tend to focus on the same few particularly attention-grabbing attributes. The knee-buckling dropshot , the outrageous will to win (and corresponding fifth-set record ), the forehands at full stretch. We don’t ask often enough why Alcaraz or Sinner won a match, because it seems obvious. They’re simply better than everybody else, except for maybe Novak Djokovic or Cameron Norrie on a good day. And it’s true, there’s no single reason why. (There’s never a single reason for anybody, though most players make it easier to isolate a small number of effective shots or tactics.) All we can do is focus on one part of the Alcaraz game, then goggle at it. Today, let’s goggle at the return of serve. Here’s a fun place to start. Djokovic completed five matches at the Australian Open. Take a look at his first-serve win percentages from those five matches: Opponent 1st W% Martinez 93.2% Maestrelli 86.0% van de Zandschulp 77.0% Sinner 71.4% Alcaraz 65.9% Djokovic, at any age, is an outstanding hard-court server. 71.4% is below average: Sinner did a nice job on return, even if he forgot on some break points. 65.9%, though, is unreal. Of the ATP top 50, how many players do you think win fewer than 66% of their first-serve points? One : Sebastian Baez. Alcaraz turned Djokovic into Sebastian Baez. It wasn’t a fluke, either. Djokovic won 66.1% of first-serve points against Alcaraz in the US Open semi-final last year. Those two aren’t the absolute worst serving performances of Djokovic’s last twelve months–Vacherot held him to 60.5% in Shanghai, and Musetti kept him to 61% in their abbreviated match–but they are close. Two separate skills Charting data allows us to break down service returns into two components: Getting serves back Winning points after getting the serve back Pretty straightforward stuff. You want to get as many serves back as possible, but you also want to set yourself up to win points after you do. There’s something of a tradeoff here. Jaume Munar is a good example of somebody who retrieves a ton of serves but loses a lot of the points because he doesn’t do enough with the return. Andrey Rublev is the opposite, not getting many returns back, but winning a relatively high percentage when he does. Adjusting for surfaces and opponent quality, the end result for Munar and Rublev is about the same, even if they get there via such different routes. The tradeoffs don’t apply to everyone. Take a look at the scatterplot, which shows percentage of returns in play, and in-play return-points won, for all ATPers with at least ten charted matches in the last 52 weeks. The higher you are above the green regression line, the better. You can mouse over each dot for player details, but I don’t need to tell you whose dots are red: ATP Returns in Play 10+ charted matches (last 52 weeks) • RiP% vs RiP Win% Sinner & Alcaraz Mere Mortals Regression Line